High frequency oscillatory apparatus for electrotherapeutic and sterilization purposes



Feb. 6, 1934. ac. RAWLS 1,945,867

HIGH FREQUENCY QSCILLATORY APPARATUS FOR ELECTROTHERAPEUTIC AND STERILIZATION PURPOSES Filed April 27, 19 32 fzzdmlar 6. fad/1: WW 7 W= Patented Feb. 6, 1934 HIGH FREQUENCY OSCILLATORY APPARA- TUS FOR .ELECTROTHERAPEUTIC AND STERILIZATION PURPOSES Paul C. Rawls, Des Moines, Iowa, assignor to Technical Equipment Company, Des Moines, Iowa, a corporation of Iowa Application April 27, 1932. Serial No. 607,775

Claims.

The object of my invention is to provide improvements in high frequency oscillatory apparatus which is particularly adapted for electrotherapeutic and sterilization purposes, and to 5 provide a comparatively simple, durable and inexpensive high frequency oscillator which may be easily and quickly connected to the ordinary alternating current light supply, and when so connected provides means whereby undampt high frequency oscillatory currents of electricity may be produced in such a manner that they may be utilized for various electrotherapeutic purposes, such for instance as surgery, electrodiathermic treatments, coagulation of tissues or blood vessels, and sterilization of animal or organic tissues; and

Further to provide a high frequency oscillator capable of producing ultra high frequency oscillatory currents considerably above the frequency heretofore utilized for therapeutic purposes, and having means whereby the amount of current and its frequency may be easily and positively varied within a wide range.

A further object is to provide in a high frequency oscillator of the type above described improved means whereby undampt high frequency currents may be produced and delivered to a suitable output circuit, and to provide in connection therewith means whereby either modulated or unmodulated oscillatory currents may be delivered to said output circuit at the will of the operator.

A further object is to provide in a high frequency oscillator of the type above described two or more output circuits controlled from a single tuned input circuit, whereby one output circuit may be utilized for surgery and the other for diathermic or sterilization purposes, so that a member being operated upon may be supported in a high frequency oscillatory electrostatic field during the time of the operation for either heating the member being operated upon or sterilizing the same to prevent infection; and

Further to provide in connection with the output circuits means .for varying the current or voltage value of one circuit relative to the other, and for independently tuning said circuits to the frequency of the input circuit.

A further object is to provide in a high frequency oscillatory apparatus of the type above described means whereby organic substances such as milk or vegetables may be rapidly and efliciently sterilized either by placing the substances in suitable containers made of insulating material and passing the same continuously through a high frequency oscillatory electrostatic field produced between spaced electrodes, or by passing the fluid substance through suitable pipes or conductors formed of insulating material and supported in said electrostatic field.

In the specification and claims by the term high frequency oscillatory electrostatic field I mean the electrical phenomenon produced between spaced electrodes in which preferably the air is dielectr'ical, and in which case said electrodes are included in an ultra high frequency oscillatory electric circuit. I find by actual experiment that if animal or organic tissues or substances are placed in a high frequency oscillatory electrostatic field, electrical energy will readily penetrate the interior of the substance so that the entire mass of substance may be equally acted upon by the electrical energy for therapeutic or sterilization purposes, and that organisms such as bacterium, spores, microbes and certain disease germs may be destroyed by applying oscillatory currents of the proper frequency without injurious effects to the tissues or substances being treated.

I have found, that it is very desirable in utilizing my improved apparatus for diathermic and other therapeutic purposes to deliver to the output circuit a high frequency oscillatory modulated current, while in surgery it is desirable that unmodulated currents be delivered to the output circuit to prevent involuntary twitching and jerking of the tissues, which would take place if modulated oscillatory currents were delivered to the output circuit.

My invention consists in the construction, ar- 0 rangement and combination of the various parts of the device, whereby the objects contemplated are attained, as hereinafter more fully set forth, pointed out in my claims, and illustrated in the accompanying drawing, in which:

Figure 1 is a diagrammatical view of my improved oscillator, showing the manner in which the double output circuit is utilized for surgery and diathermic treatments.

Figure 2 is a detail diagrammatical view illustrating anothermethod of applying the double output circuit for surgery and coagulation.

Figure 3 is a side elevation of my improved means for sterilizing substances supported in containers formed of insulating material, such as bottled milk.

Figure 4 is an end elevation of the same showing the manner in which the apparatus is connected in one of the output circuits of the oscillator.

Figure 5 is'a modified form of a sterilizing device to be used in the sterilization of liquids.

Figure 6 is an end elevation of the same showing the manner in which the device is included in one of the output circuits of the oscillator.

Referring to the accompanying drawing, I have used the reference numeral 10 to indicate a wall plug included in an alternating current lighting system, and 11 a conductor leading to the fuse panel 12, and also to a conductor 13 o! the transformer coil 14. The conductor 13 is connected to a conductor 15, one end of which is connected to a transformer winding 16, said winding also being connected to a conductor 17 in which is included a switch arm 18 adapted to make contacts with taps 19 of the coil 16.

The other end of the conductor 17 is connected to a conductor 19a which in turn is connected to one of the members of the conductor 11. The other end of the conductor is connected to one end of a primary winding 20 and also to the time relay 21. The other end of the primary 29 is connected to the time relay by means of a tap switch device 22.

The relay 21 provides means whereby the coil 20 will be automatically connected into the supply circuit after the filaments of the oscillator have become heated. A filament coil 23 is in ductively connected to the coil 16 and is provided with conductors 24 and 25. Each of said con ductors includes a choke coil 26, said chokes being connected to the conductors 27 and 28 which in turn are connected to the filament oi the vacuum tubes 29, said filaments being connected in parallel as clearly illustrated.

The coil 23 is provided with a center tap 36 to which a conductor 31 is connected. Fixed condensers 32 are supported between the conductors 27 and 28 and the conductor 24. Each 01 the tubes 29 is provided with a grid 33. A conductor 39. The inductance w is inductively coupled.

with the inductance coil 35 in such a manner that the tuning condenser 36 is employed for tuning the plate circuit.

Inductively coupled to the coil 39 is an output coil 49 having terminal members 51 and 4 2. Connected in the center of the coil i0 is a variable condenser 44. Also inductively connected to the plate coil 35 is an auxiliary output coil 45, having terminals 46 and 47. The inductance has taps 48 and switch devices 4.9 whereby the number of active coils of inductance may be increased or decreased to obtain various voltage values in the auxiliary output circuit.

Inductively coupled with the coil 14: is a filament coil 52 having conductors 53 leading to the conductors 54, which in turn are connected to the filaments of the rectifying tubes 55.

Inductively coupled to the coil 20 is a high voltage coil 56 each end of which is provided with 'a conductor 57 connected to the plates 58 of the tubes 55. The coil 56 is provided with a center tap 59 to which a conductor 60 is connected. Said conductor 60 makes connection with a terminal 61 of a filter block 62 which is of the ordinary type designed to smooth out the high voltage alternating current oithe coil 56 and to deliver to the plate coil 39 unmoduconnection with the terminal 71 of the filter block II the switch arm is caused to engage the terminal 66, then unmodulated high voltage and rectified current will be delivered to the plate coil; while if the switch arm 65 is caused to engage the contact 68, then unfiltered alternating current will be delivered to the plate coil 39, thereby providing means whereby the operator may deliver to the plates of the tubes 29 either high voltage unmodulated direct current or high voltage alternating current simply by operating the switch 65.

Thus it will be seen that I have provided a high frequency oscillator of the vacuum tube type in which comparatively simple means is provided for tuning the grid and plate circuits, which consists of the input circuits or the output coils 39 and 45, and I have provided in connection therewith means whereby either alternating current or direct current may be applied to the plates of the oscillation tubes 29 at the will of the operator. the normal working voltage of the coil '56 may be increased or decreased. In a like manner the tapped coil 16 provides means whereby the fila= ment voltage of the coil 23 may be increased or decreased.

It is sometimes desirable to employ two output circuits in electrotherapeutic operations, in which case both the auxiliary output coil d5 and the output coil 40 are employed.

In Figure 1 I have illustrated one manner in which both or the output circuits may be ern plcyed in surgery. The terminal 42 is provided with a conductor '76, which terminates in a terminal plate 7'7 supported beneath an insulator member 78, such as a glass-plate.

The anatomical member '79 to be operated upon is placed on the plate 78. The operating instrument 80 is preferably provided with an insulated handle 81 so that the metallic part of the instrument is insulated from the operators body. The operator's body serves as an energy collecting or absorbing'medium for receiving energyfrom the terminal 41 and delivering it to the instrument 80 through capacity coupling between the instrument and the operators body.

As soon as the instrument 89 is-placed near the anatomical member to be operated upon, an electrostatic field will then be established between the plate 7'7 and the instrument, the energy of which will penetrate the tissues of the body 79 in a concentrated manner to cause the tissues to be separated'without actually outing the same and without burning or carbonize- .tion of the separated surfaces.

When the instrument 80 is used for severing live tissues, it is essential that the switch member 65 be moved into contact with the member 66 to deliver unmodulated current to the plate of the tubes 29, the plates of which will deliver to the output ,circuit a high frequency oscillatory unmodulated currents, as I find that ii the high rrequency' oscillatory modulated current is deliv- The tapped coil 26 provides means whereby I ered to the member 80. then twitching of the muscles of the tissues will result as the cutting energy engages the nerves. This twitching action is entirely avoided by using the unmodulated current.

In this connection it should be noted that both the instrument 80 and the body being treated are absolutely insulated from the oscillatory currents, so that no actual current is delivered through the operating instrument or through the tissue being operated upon from the terminals 41 and 42. If the proper amount of current is applied at the same time the separating action takes place, then a slight coagulation will take place to prevent the flow of blood from the blood vessels. v

If the anatomical member is placed a considerable distance from the generator, then it may be necessary to provide a conductor 81 illustrated by dotted lines, one end oi. which-may terminate near the operator for delivering energy to said operator.

Sometimes it is desirable to administer diathermic treatment simultaneously with the surgical operation. This may be accomplished by connecting to the terminal 46 a conductor 82 having a terminal plate 83, said plate being completely insulated but conductively connected to said conductor. The said plate is placed adjacent to one side of the member '19 in the manner clearly illustrated. The terminal 47 is provided with a conductor 84 terminating in' a terminal plate 85 which is also completely insulated. Said plate 85 is placed on the opposite side of the member 79 from the plate 83, there- 'by providing means whereby a high frequency oscillatory electrostatic field may be established between the plates 83 and 85, in which the member 79 is supported, and whereby sterilization of the member may take place simultaneously with the operation. A variable condenser is connected to the conductors 82 and 84 for controlling the flow of current in the coil 45.

The output circuit includes the condenser 44 by means of which the frequency of said output circuit may be tuned to the frequency of the input circuit after the anatomical member has been placed in position.

Sometimes it is desirable to provide one instrument for separating the tissues and another one for coagulating the larger blood vessels and the tissues to be severed before the severing operation takes place, and to operate the two instruments simultaneously, in which case the instruments are connected in the circuit in the manner illustratedin Figure 2, in which the Plate 77 is connected to. the terminal 42 in the manner above described, the plate 85 being eliminated. The tool is operated in the manner before described.

A tool 51 may be provided for coagulation, said tool being connected to the conductor 84.

In operation the instrument may be first drawn over the surface to be separated, causing a deep penetrated coagulatedarea, which may then be severed by the tool 80, the member 85 may be in the form of a hemostat, which may be applied to the larger blood vessels after the tissues have been severed from around them, causing that portion of the .blood vessel engaged by the hemostat to be coagulated and the blood flow stopped, after which the blood vessel may be severed without bleeding and without tying 05.

By this arrangement it will be seen that con-' siderable time may be saved, inasmuch as one operator may handle the instrument 80 first severing the tissues around the larger blood vessels, and another operator may handle the instrument 85 and coagulating the blood vessels. Sometimes it is desirable to change the current value of the auxiliary output circuit which may be easily and quickly accomplished by controlling the condenser 50. This condenser may also be used to control current of the output coil 40, as it will readily be seen that loading the auxiliary output circuit will rob the grid 35 and cause a reduction in the plate coil 39, and in turn the energy transferred to the coil 40, or vice versa. I

I have also discovered that if bottled milk and similar substances are supported in a high frequency oscillatory electrostatic field, which is oscillated at certain frequencies in which the proper current value is placed in the oscillatory circuit, said milk or similar substance may be sterilized while in the air tight containers, and

' that the said containers may be filled and sealed and then passed successively through the electrostatic field in such a manner that they may be sterilized in a continuous operation.

In Figures 3 and 4 I have illustrated a simple apparatus in a diagrammatic manner for accomplishing this purpose, in which the numera1 indicates a continuous conveyor supported by rollers 91, the top run of the conveyor being supported between the lower edges of the upright and longitudinally extending electrodes 92, said electrodes being entirely insulated by insulating material 93 to prevent the operator from making electrical contact with the electrodes, and thereby preventing severe burning.

An electric motor or other suitable means 94 is provided for continuously operating the conveyor 90 in such a manner that bottles of milk 95 placed on the receiving end of the conveyor in an upright position will be caused to pass between the electrodes 92 and through the electrostatic field established between said electrodes. The electrodes 92 are provided with conductors 96 and 97, which are connected to the terminals 42. The condenser 44 is placed in series with the coil 40 instead of parallel as illustrated in Figure 1. A meter 98 may be placed in the circuit for determining whether said circuit is in resonance with the input, and also for determining the amount of current flow.

I have also found that in sterilizing milk and other substances it is essential that the oscillation be maintained at a constant current value and at a constant frequency.

In Figures 5 and 6 I have illustrated a slightly modified form of apparatus for sterilizing fluids, which comprises a pair of spaced electrodes 99 included in the output circuit. The said electrodes 99 are also insulated and spaced apart to form an electrostatic field between them when oscillatory currents are established in the output circuit. A container 100 is provided for receiving the milk or fluid which is delivered through an outlet pipe 101 in which a control valve 102 is included. Extending downwardly from the valve '102, is a pipe 103 which is bent laterally and then the coils 104, which are supported in the electrostatic field. The electrical energy penetrating the tube member formed of insulating material and the fluid within the coil.

It will readily be seen that other substances than milk may be sterilized by means of my improved apparatus, sterilization taking place without increasing the temperature of the material being sterilized to any great degree. In this manner my improved sterilizing apparatus differs from methods of-sterilization heretofore used wherein it is necessary to heat the milk or other substances to a comparatively high degree in order to kill bacteria and ferments.

Suitable instruments 106 are employed in the various circuits for determining the voltage and amperes of the circuit, and for determining when the input and output circuits are in resonance.

In the drawing and specifications I have illustrated two methods of inserting the anatomical member in the electrostatic field, both of which include simultaneously the two output circuits. However, it will readily be seen that operations may be performed either with one of the output circuits or that the auxiliary output circuit may have a different current and voltage value from the main output circuit, and that one of the output circuits may be utilized for one kind of treatment and the other output circuit for another kind of a treatment by simply making connection with the proper output terminals.

It will also be readily seen that the cutting instrument 80rnay be connected directly to the conductor 81 if so desired. However, I find that it is more satisfactory to couple the instrument to said conductor or the terminal 41 capacitively.

By providing the filter block in the plate circuit, and the switch member 65 together with the conductor 69, l have provided means whereby either modulated or unmodulated plate currents may be delivered to the plates of the oscillation tubes, whereby either alternating current or unmodulated direct current may be delivered to the output circuits at the will of the operator.

I claim as my invention:

1. In a device of the class described, the combination of a driver circuit, means for producing high frequency currents of electricity of predetermined frequency in said circuit, a pair of output circuits inductively coupled to the first circuit, said outputcircuits each having means for ineluding an anatomical member, a therapeutic instrument in one of said output circuits, means for tuning each of said output circuits independently of the other and to the frequency of said driver circuit, whereby diathermic treatments may be administered to a patient by one of said output circuits simultaneously or independently with a surgical operation administered by energy derived from the other output circuit.

2. In a device of the class described, the combination of a driver circuit, means for producing a high frequency oscillatory current of electricity of predetermined frequency in said circuit, a pair of output circuits coupled'to the fi'rst circuit, each circuit having means for including an anatomical member, a therapeutic instrument in each circuit, means for tuning each of said output circuits independently of the other to the frequency or said driver circuit after the anatomical member has been included, and means for changing the current value and potential of one of the output circuits relative to the current value and potential of the other circuit, whereby two kinds of electrotherapeutic treatments may be administered simultaneously to said anatomical member.

3. In a device of the class described, a driver circuit, means for producing ultra high fre= quency oscillatory currents of electricity in said circuit, means for changing the frequency of said circuit, an output circuit coupled to said cir= cuit, means in said output circuit for includin an anatomical member, said means including spaced electrodes, one of said electrodes being adapted to be placed adjacent to an antomicai member to be treated and insulated therefrom, an electrotherapeutic instrument formed of conducting material non-conductively included in said circuit between said electrodes, one end of said conducting material being covered with. insulating material to form a handle whereby an operator grasping said handle will'be capacitiveiy included in said circuit, and means for tuning the frequency of the output circuit after the operator and anatomical member has been included therein.

4. In an apparatus for producing ultra high frequency oscillatory currentsof electricity for therapeutic purposes, comprising in combina tion an alternating current supply, a rectifying circuit coupled thereto, a filter circuit connected to said rectifying circuit, an ultra high frequency generator of the vacuum tube type including grid and plate circuits inductively coupled to each other, means for tuning said circuits to a pre determined frequency, a treating circuit coupled to said grid and plate circuits adapted to include a therapeutic instrument, means for tuning the frequency of the treating circuit, means for operatively connectingeither the rectifying cir cult or the filter circuit to said plate circuit, whereby either modulated or unmodulated direct current may be applied to said plate circuit.

5. In an apparatus for producing ultra high frequency oscillatory currents of electricity for therapeutic purposes; comprising in combination an alternating current supply, a rectifying circuit coupled thereto, a filter circuit connected in said rectifying circuit, an ultra high frequency generator of the vacuum tube type including grid and plate circuits inductively coupled to each other, and means coupled to said alterhating current supply for supplying filament current to the vacuum tubes of said generator, means for varying the voltage of said filament supply, means for varying the voltage applied to said rectifier circuit, means for tuning said plate and grid circuits to a predetermined frequency, a treating circuit coupled to said plate circuit adapted to include a therapeutic instrument, means for tuning the frequency of said treating circuit, and means for operatively connecting either the rectifying circuit or the .filter circuit to said plate circuit, whereby either modulated or unmodulated direct current will be applied to the plate circuit.

PAUL C. RAWLS. 

